Message-register circuits.



A. E. LUNDELL.

MESSAGE REGISTER CIRCUITS,

APPLICATION FILED OCT. 2, I916- 1,222,31 1., malted Apr. 10, 1917.

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ALBEN a. LUNDELL, or new Yoair, N. 2., assrencn To wnsrnnu nnncrnrc conraur,

INCORPORATED, on NEW roan, N. in, a conronarronor new YORK."

MESSAGE-REGISTER CIRCUITS.

Specification of Letters Patent. Patented Apr. it), 11911 *7 Application filed October 2, 1915. SeriaLNo. 123,314.

To all whom it may concern:

Be it known that I, Annex E. LUNDELL, a citizen of the United States, residin at New York, in the county of Bronx and ta te of New York, have invented certain new and useful Improvements in Message-Register Circuits, of which the following is a full, clear, concise,,and exact description. v

This invention relates to telephone systems, and more particularly to such systems of the measured service type.

In systems heretofore used in. which message registers or service meters associated with line circuits were employed, the operation of the register changes the potential of the test terminal of the line. This condition has made it extremely diflicult to obtain a test relay for use in the connecting circuits which would function properly under the conditions of test terminal potential existing both before and after the operation of the message register. The object of the present invention is the production of a system in which these difliculties will be obviated. Preferably this is accomplished by so organizing the message register and its controlling circuit that the potential of the test terminal of the line is not changed after the operation of the message register.

For a more complete understanding of this invention, reference should be had to the following description taken in connection with the drawing, wherein is shown so much of a telephone exchange system as is necessary to illustrate the invention.

Before proceeding with the operation of the system, a word of explanation regarding the message registermay be in order. Associated with the telephone line A is a message register M, having a controlling electromag net 6 having high and lower-resistance windings 7 and 8. These windings are connected with the sleeve or test terminal 9 of line A. The electromagnet 6' controls an armature 10, to whichis pivoted a pawl 11 for actuating a counting train 12. When a circuit through the windings 7 and 8 from the usual central office battery is completed, the armature 10 will not be attracted, but when a message register battery 13 is included in circuit with the windings 7 and 8, the armature 10 is attracted to actuate the eat ng l the arm tu fi 10 is attracted, a projection 14 carried thereby engages a contact'spring 15 which thereupon engages a contact"20 to establish a short circuit for the high-resistance winding 7 to control other apparatusas will hereinafter more fully appear. When the battery 13 is removed from this circuitfthe armature 1 0 is retracted under the action 'of springs 21 and 22 to an intermediateposi tion with contact 20 and contact spring 15 out of engagement, but the pawl 11 'does'not drop back to the'next toothof the ratchet wheel of the counting train 12. The armature 10 is maintained in this position until the circuit throughthe windings 7 and 8, is opened, when the spring 22 returns the armature 1 0 to normal position with the pawl 11 in engagement with the next tooth, preparatory to, registering another call. The operation of the system is as follows: subscriber A, desiring to converse'with subscriber B, removes 'the receiver from the switchhook, causing thelighting of the line signal in the usual manner. The operator then inserts the answering plug of cord circuit G into the jack associated with Asline, whereupon relay 30 and cutoff relay 31 are operated over a circuit from battery, through the winding of cutoff relay 31, sleeve contacts of the answering jack and plug, normal .contact of key 32, and the winding'of relay 30 toground. A circuit from battery, through both the highand low-resistance windings of electromagnetfi, in parallelwith thewinding of cutofi' relay 31, is also completed, but the electromagnet 6 is not sufficiently energized by the regular central oflice battery'to attract its armature 10, The operation of relay 30 completesa circuit for lamp 33, which thereupon lights and remains lighted until talking connection is established with the station connected with line B. The connection between the cord circuit C and lineB may be by means of a calling plug and jack, or by means of automatic apparatus. This is not essential, since it forms no part of the present invention. Likewise, the station of line B may be signaled in any desired manner; l/Vh'en the subscriber at the station of line B responds by the removal of'the' receiver from the switchhook, supervisory relay 3 l is ene z d, t ereup n ex ing l p 33, which is a signal for the operator that the call originating on line A may now be registered. This is accomplished by the actuation of key 32 which opens its normal and closes its alternate contact, thereby causing the electromagnet 6 of the message register M to attract its armature 10 and actuate'the counting train 12. The operating circuit for electromagnet 6 may be traced from battery 13, through the winding of marginal relay 35, alternate contact of key 32, sleeve contacts of the answering plug and answering jack, windings 8 and 7 0f electromagnet 6, and through the usual central ofiice battery to ground. Relay 35 is marginal so that it does not operate when in circuit with both the high and low-resistance windings 7 and 8 of electromagnet 6, but does operate when in circuit with the low resistance winding 8 only. The armature 10, in being attracted, causes the engagement of contact spring 15 with contact 20, thereby short-circuiting the high-resistance winding 7, whereupon marginal relay 35 operates to cause lamp 36 to light, indicating to the operator that the call has been registered. The operator may now restore key 32 to its normal position, whereupon marginal relay 35 releases. When key 32 is restored to its normal position, the armature 10 of the message register M will assume an intermediate position, removing the short circuit from the high-resistance winding 7, but not permitting the pawl 11 to drop back far enough to engage another tooth of the ratchet wheel of the counting train 12. In this way, that is by the removal of the short circuit from the high-resistance winding 7 after the opera tion of the register, the potential of the sleeve test terminal of the answering jack and terminals in multiple thereof is the same both before and after the operation of the message register. In addition to this, since the pawl 11 is not permitted to drop back to engage another tooth, it will not be possible to cause a false operation of the message register.

As before indicated, the terminals of line A may be multipled to other operators positions or, as indicated in the drawing, to terminals 40, 41 and 42 of a finder switch F. Associated with the test brush 43 of the finder switch F is a test relay 44 which has a low-resistance winding 45 and a high-resistance winding 46. Winding 45 of this test relay is of the same resistance as the winding of relay 30. While the answering plug of the cord circuit is inserted in the jack of line A, should a call be received for line A, the test brush 43 of finder switch F will move over terminal 42, and test relay 44 will not be operated for the reason that this relay does not pull up when its two windings are connected in parallel with the winding of relay 30 or when in parallel with the low-resistance winding 45 of another test relay 44.

What is claimed is:

1. A telephone system comprising a telephone line, a service meter therefor, a double wound electromagnet and armature therefor for operating the meter, an operating circuit for the electromagnet, means for completing the operating circuit, a short circuit for one winding of the electromagnet established upon operation of the electromagnet, a holding circuit for theelectromagnet established upon the subsequent opening of the operating circuit, and means cooperating with the armature upon the establishment of the holding circuit to move the armature into an intermediate position and open the short circuit.

2. A telephone system comprising a tele-- phone line, a service meter therefor, a double wound electromagnet and armature therefor for operating the meter, an operating circuit for the electromagnet, means for completing the operating circuit, a short circuit for one winding of the electromagnet established upon operation of the electromagnet, a holding circuit for the electromagnet established upon the subsequent opening of the operating circuit, and a spring cooperating with the armature upon the establishment of the holding circuit to move the armature into an intermediate position and open the short circuit.

3. A telephone system comprising a telephone line, a service meter therefor, an electromagnet and armature therefor for operating the meter, a normally open operating circuit for the electromagnet, means for closing the operating circuit, means actuated upon the movement of the armature for decreasing the resistance of the operating cir cuit, a holding circuit for the electromagnet established upon the subsequent opening of the operating circuit, and means cooperating with the armature upon the establishment of the holding circuit to move the armature into an intermediate position and to again actuate the second-mentioned means to increase the resistance of the holding circuit.

4. A telephone system comprising a telephone line, a service meter therefor, a double wound electromagnet and armature therefor for operating the meter, an operating circuit for the electromagnet, means for completing the operating circuit, a short circuit for one winding of the electromagnet established upon operation of the electromagnet, a holding circuit for the electromagnet established upon the subsequent opening of the operating circuit, and means operating upon the establishment of the holding circuit to open the short circuit.

5. A telephone system comprising a telephone line, a service meter therefor, a double wound electromagnet and armature therefor for operating the meter, an operating cirating With the armature upon the establishcuit for the electromagnet, means for comment of the holding circuit to open the short 1 O pleting the operating circuit, a. short circuit circuit. for one Winding of the electromagnet es- In Witness whereof, I hereunto subscribe 5 tablished upon operation of the electromagmy name this 29th day of September A. D.,

net, a holding circuit for the electromagnet 1916. established upon the subsequent opening of the operating circuit, and a spring cooper- ALBEN E. LUNDELL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. U. 

